
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>运动框架（面向对象版）</title>
<style>
body,div{margin:0;padding:0;}
#wrap{width:500px;margin:10px auto;}
.box{position:relative;height:100px;border:1px solid #666;margin-top:10px;}
.box span{position:absolute;top:10px;left:10px;width:20px;height:20px;background:#999;display:block;opacity:1;}
</style>
<script type="text/javascript">
//面向对象版运动框架
var Animate = function (oElement, options, callback) {this.initialize.apply(this, arguments)};

Animate.prototype = {
	initialize: function (oElement, options, callback)
	{
		var oThis = this;
		this.options = options;
		this.callback = callback;
		this.oElement = typeof oElement === "string" ? document.getElementById(oElement) : oElement;
		clearInterval(this.timer);
		this.timer = setInterval(function ()
		{
			oThis.doMove()
		}, 30)
	},
	css: function (attr, value)
	{
		if (arguments.length == 1)
		{
			return parseFloat(this.oElement.currentStyle ? this.oElement.currentStyle[attr] : getComputedStyle(this.oElement, null)[attr])
		}
		else if (arguments.length == 2)
		{
			attr == "opacity" ? (this.oElement.style.filter = "alpha(opacity=" + value + ")", this.oElement.style.opacity = value / 100) : this.oElement.style[attr] = value + "px"
		}
	},
	doMove: function ()
	{
		var opt = this.options;
		var bComplete = true;		
		for (var p in opt)
		{
			var iCur = p == "opacity" ? parseInt(this.css(p).toFixed(2) * 100) : this.css(p);
			var iSpeed = (opt[p] - iCur) / 5;
			iSpeed = iSpeed > 0 ? Math.ceil(iSpeed) : Math.floor(iSpeed);
			opt[p] == iCur || (bComplete = false, this.css(p, iCur + iSpeed))
		}
		bComplete && (clearInterval(this.timer), this.callback && this.callback.call(this))
	}
};
//运动框架应用
window.onload = function ()
{
	var oSpan = document.getElementsByTagName("span")[0];
	var oInput = document.getElementsByTagName("input")[0];
	//定义运动路径
	var aData = [
		{width:20, height:20},
		{width:80, height:80},
		{left:10}, {left:408},
		{opacity:100},
		{opacity:0},
		{opacity:100},
		{width:80, height:80, left:408},
		{top:10},
		{width:20, height:20, left:468},
		{top:70},
		{left:10},
		{top:10},
		{left:468},
		{width:20, height:20, left:468},
		{width:80, height:80, left:408}
	];
	var bOrder = true;
	var i = 0;
	oInput.disabled = false;
	//按钮点击事件(开始/返回)
	oInput.onclick = function ()
	{
		var oThis = this;
		oThis.disabled = true;
		function begin()
		{			
			bOrder ? i++ : i--;
			var obj = new Animate(oSpan, aData[i], begin);			
			if (i == aData.length || i < 0)
			{
				clearInterval(obj.timer);
				bOrder = !bOrder;
				oThis.value = bOrder ? "\u5f00\u59cb" : "\u539f\u8def\u8fd4\u56de";
				oThis.disabled = false;
				return
			}
		}
		begin()
	};
	//去除按钮虚线
	oInput.onfocus = function ()
	{
		this.blur();	
	}
}
</script>
</head>
<body>
<div id="wrap">
    <input type="button" value="开始" />
    <div class="box"><span></span></div>
</div>
</body>
</html>
